This invention was supported by Samsung Research Funding Center of Samsung Electronics under Project Number SRFC-IT1401-09.
Hand-over, extensively employed in mobile telecommunications, is an essential technology to continuously provide users with services in a network that experience frequent changes. In short, hand-over is used in a cellular network to provide users with continuous communication. For example, hand-over occurs when a base station that is connected with a mobile station is changed because the wireless channel status in the base station is at fault or the mobile station moves from a base station area to another base station network, wherein although the user moves, the base station, installed on the ground, has a fixed cellular network.
Hand-over is also used to continuously provide a WLAN such as WiFi, for which the APs (access points) of all the WLANs have been operated in NAT (network address translation) mode and virtual router technology has been introduced to provide mobile telecommunications only by WLANs by overlapping the APs like mobile telecommunications base stations. An AP, however, has a diameter of about 20 to 30 m only, which is not very practical making the service available only in an area where there is a large transient population with also a significant number of APs installed.
As thus far described, hand-over that occurs in a cellular network or WLAN takes into consideration only the mobility of users with base stations or APs fixed as well as an service area also fixed, wherein the base stations are fixed on the ground with no mobility while environments such as power supply are stable, which means almost no change in the network.
A drone network that provides users with its services under special conditions, where frequently drones are replaced or drones moves in formation depending on whether there is a user or according to the drone status, is not conformable to such existing hand-over technology. In other words, no hand-over technology has ever been developed to provide stable network services under a condition that the network is configured in the air and per se highly mobile.